Casemiro is 28, and Ramos will surely play at a more than acceptable level for two seasons.Dare I say it. He's in a better position he'll find anywhere else in terms of legacy and even money.
We've got Rashford, 22 years old, Martial 24 years old, Greenwood 18 years old, Bruno Fernandes 25 years old while he - himself, is 27 years old. Maguire 27 years old, Williams 19 years old, Wan-Bissaka 22-years old. Goalkeeping position is sorted with De Gea/Hendersson + Kovar - any way it turns out.
He'll do what he wants to, but he, in terms of legacy, wont do himself any favours jumping ship again especially in this era unless he wants to be paid more and he's already getting paid plenty. I genuinely believe he's here to stay. The only teams he could go to is PSG and Ligue 1 is not up to standards anyway and PSG will always struggle abroad. Real Madrid with Ramos about to retire, Kroos to be 31.. Modric turning 35, Casemiro 33.. Hazard 29 for a winger. Benzema 33 this year. Bale is done and dusted.. turning 31. Good luck replacing all those in this era.
His best shot unless he only aims for money is United at this point unless he signs for a chinese club. He knows that. Covid-19 and all these other factors makes it a given.
If he comes it is precisely to replace Modric.
Kroos may be a problem, but not in the immediate present. On the other hand we have Fede Valverde, Vinicius, Rodrygo, Odegaard or Take Kubo (these two in the medium term).
Carvajal, Varane, Asensio, Courtois are still young.
I agree on the subject of Benzema, and more seeing Jovic's failure. However it is valid if we think that the only factor he takes into account for his renewal is "appearance / future" of the team.
He's 27, like Modric when he came. He has enough time to create a new legacy, or expand the one he already has.
As you say the Covid changes everything. I don't know if it is very appropriate/feasible to spend so much money while employees cut their wages by 10%.
Of course they would have to sell and get rid of James and Bale's salary.